Pity the protons: Those little particles are under a lot of pressure. Protons’ innards are squeezed harder than any other substance we have measured, a new study finds.

“It’s really the highest pressure we have ever seen,” says physicist Volker Burkert, a coauthor of the study, published in the May 17 Nature. Protons break the pressure record set by neutron stars, the incredibly dense...

Protons are no one-trick ponies. Although famous for their positive electric charge, the particles also carry an analogous, lesser-known charge, called the weak charge. Now, physicists have made the most precise measurement of the proton’s underdog attribute, members of the Q-weak experiment report in the May 10 Nature.

The weak charge dictates how the proton responds to the weak nuclear...

Physicists are ramping up their search for neutrinoless double beta decay, which could help explain why there is more matter in the universe than antimatter, Emily Conover reported in “The quest to identify the nature of the neutrino’s alter ego is heating up” (SN: 3/17/18, p. 14).

Reader F L Stiles wondered how this decay could explain a surplus of matter. “It...

Scientists playing peekaboo with dark matter have entered a new stage of the game.

For the first time, physicists are snooping on some of the likeliest hiding places for hypothetical subatomic particles called axions, which could make up dark matter. So far, no traces of the particles have been found, scientists with the Axion Dark Matter Experiment, ADMX, report April 9 in Physical...

Inspired by flatworm memory experiments from the 1950s, researchers are on the hunt for the elusive engram — the physical mark that a memory leaves on the brain — Laura Sanders reported in “Somewhere in the brain is a storage device for memories” (SN: 2/3/18, p. 22).

Readers flooded Science News with their thoughts and questions on the topic.

Galaxies, stars, planets and life, all are formed from one essential substance: matter.

But the abundance of matter is one of the biggest unsolved mysteries of physics. The Big Bang, 13.8 billion years ago, spawned equal amounts of matter and its bizarro twin, antimatter. Matter and antimatter partners annihilate when they meet, so an even stephen universe would have ended up full of...

Not all fundamental forces are created equal. An alternate universe that lacks the weak nuclear force — one of the four fundamental forces that govern all matter in our universe — could still form galaxies, stars, planets and perhaps life, according to calculations published online January 18 at arXiv.org.

Scientists have long thought that our universe wouldn’t exist, or at least wouldn’...

It’s three for the price of one. A trio of mysterious high-energy particles could all have the same source: active black holes embedded in galaxy clusters, researchers suggest January 22 in Nature Physics.

Scientists have been unable to figure out the origins of the three types of particles — gamma rays that give a background glow to the universe, cosmic neutrinos and ultrahigh energy...